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I’ve been gradually replacing my plastic containers with glass ones. For something I use every day, I wanted something comfortable to use. These are the ones I chose.

Why HARIO

HARIO has been making heatproof glass in Japan since 1921 — starting with laboratory glassware, where precision and quality were everything. That same standard carries through to their everyday products today.
The name itself means “King of Glass,” and they live up to it: all glass is made from 100% natural minerals, and since 1972, their factory has operated without smokestacks — a commitment to the environment that was well ahead of its time.

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What It’s Like to Us

I use them throughout the day, in different sizes — the smaller ones for rice or dipping sauces, sometimes for biscuits or chocolate with tea.

Biscuits in a small glass container, with a HARIO mug.

The medium size works well as a salad bowl or rice bowl, and the larger rectangular ones are useful for fish dishes.

Ingredients prepped in HARIO glass containers before making fried rice.

I like that I can place them directly on the table and use them as they are.

Unlike plastic, I can heat them straight in the microwave without transferring to another dish, and they don’t absorb odors or stains.

They also feel solid and durable. I sometimes knock them lightly while washing or drying, but I haven’t had a single one break.
On busy days, it helps that I can just use them without thinking too much.

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Key Details

• Made in Japan
• Made from natural materials (no heavy metals)
• Oven and microwave safe
• Dishwasher safe

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Things to Keep in Mind

• The lid isn’t fully airtight
• The lid should not be used in the microwave

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Where to Buy

→ The HARIO Glass Storage Containers I Use (Amazon US)

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Related Articles

→ The HARIO Glass Teapot and Mug I Use Every Day
→ The HARIO Glass Storage Containers I Use Every Day

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Closing

It’s a simple glass container, but one I reach for every day.

A tawashi is a traditional Japanese scrubbing brush used for cleaning cookware, vegetables, and kitchen tools.

The oval-shaped Kamenoko tawashi was invented in 1907 by Nishio Shoten in Tokyo, and is still widely used today.

Kamenoko tawashi literally means “baby turtle tawashi.”
The oval shape was said to resemble a small turtle.

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How it differs from Western scrubbers

In many Western kitchens, natural fiber brushes are used too — but they tend to be purpose-specific. A vegetable brush for produce, a dish brush for cookware, a nail brush for hands.

A tawashi is a little different.
One brush can move from cast iron pan to root vegetables to sink drain — without skipping a beat.

That versatility, combined with its durability, is what has kept it in Japanese kitchens for over a century.

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Types of tawashi

Kamenoko Tawashi and Karukaya Tawashi

Palm (coconut fiber)

The firmest and most durable.
Firm, springy fibers remove burnt-on residue and oily buildup from iron plates and grills.

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Shuro (palm bark fiber)
Balanced in firmness, with resilient yet flexible fibers. Gentle on surfaces, it cleans without scratching.
Suitable for glass, ceramics, and non-stick pans.

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Sisal
The softest fibers among the four. Gently wipes away residue rather than scraping it off.
Suitable for non-stick pans, plastic containers, sinks, and bathtubs.

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Karukaya

Thick, firm, and durable fibers that don’t absorb oil easily. Removes burnt-on and stuck-on food from cast iron pans.
Dries quickly after use.

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How to Use Tawashi

I mainly use a karukaya brush for my cast iron pan.
Because it’s made from natural fibers, it doesn’t strip away too much of the oil layer, and it’s less likely to scratch the surface.

Its slim shape also makes it easy to hold.

Pots and pans are often washed
with just water and a tawashi.

For root vegetables such as burdock and potatoes, I use the oval-shaped tawashi.
The firm fibers help remove dirt effectively, and using natural materials feels more suitable for something that comes into direct contact with food.

A tawashi is perfect for cleaning
soil-covered vegetables like burdock root.

Tawashi are also useful beyond the kitchen.

They work well for cleaning stove grates, drains, shoes, and even outdoor surfaces.
Because they are durable and versatile, they rarely get thrown away after kitchen use — they simply move on to the next job.

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Where to Buy

Available on Amazon US.
→ the palm tawashi on Amazon
→ the karukaya tawashi on Amazon

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Related Articles

→ A Cast Iron Pan for Everyday Cooking
→ River Light Iron Frying Pan Review — A Japanese Pan I Keep Using
→ How to Care for a Cast Iron Pan
→ Karukaya Brush for Cast Iron Pans — A Natural Scrubber from Japan

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Closing

A simple tool, quietly used in everyday life.

Washing the pan with water and a natural fiber brush.

Cast iron pans have been used for centuries — long before modern coatings and special treatments existed.

They are often thought to be difficult to maintain — easily rusted, hard to clean, and requiring special treatment after every use.

In reality, their care is quite simple once you understand a few basic routines. This is how I care for mine.

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Transfer the food shortly after cooking

Leaving food in the pan for too long can make it more prone to rust, especially when the dish contains acid or salt.

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Wash the pan with water and a brush

Cast iron pans are generally washed without detergent.
This helps the surface gradually build its natural oil layer over time.

Instead of a sponge, a scrubbing brush or a traditional tawashi works better for removing residue. Unlike coated pans, cast iron has no surface treatment to protect, so you can scrub it firmly without worry.

If food is badly stuck or there is stubborn residue, add some water and bring it to a boil. Let it sit for a moment to loosen the residue, then scrub it away.

I use a karukaya brush for everyday washing.
You can read more about it here.
→ Karukaya: A Simple Brush for Cast Iron

That said, if you are concerned about oil buildup, washing occasionally with a small amount of dish soap is fine.
The oil layer, once properly formed, is more resilient than it might seem.
→ Why My Iron Pan Is Turning Black

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Dry the pan thoroughly

After washing, wipe away the moisture with a paper towel or place the pan over heat to evaporate any remaining water.

If wiping leaves dark marks on the paper towel, it’s simply iron and oil from the surface — nothing harmful.

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Apply oil when necessary

Because the pan is generally washed without detergent, oil gradually settles into the surface over time. Even if you occasionally wash it with detergent, the pan will still continue to develop seasoning through regular cooking and heating. For this reason, there is no need to apply oil after every use.

However, if the pan will not be used for a long period, apply a thin layer of oil before storing to help prevent rust.

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Burn off stubborn residue

If stubborn residue remains even after scrubbing with a natural brush, place the pan on the stove and heat it for about 10 minutes. Use moderate heat so the pan does not smoke excessively.
This burns off the stuck residue.

After letting the pan cool slightly, scrub it with a copper or stainless steel scrubber.

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If Rust Appears

If reddish-brown rust appears on the surface, scrub it off with a copper or stainless steel scrubber.
Wash the pan thoroughly, dry it completely, and apply a thin coat of oil and heat the pan to re-season.
The pan can still be used — rust does not mean the pan is ruined.

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Closing

Over time, these small routines simply become part of cooking.

The pan slowly builds its surface, and before long, it becomes a tool you reach for without thinking.

Quiet, simple cookware meant to stay in the kitchen for years.

Why Food Sticks

Food sticks when the pan isn’t preheated enough or when there isn’t enough oil. Without enough heat, food bonds to the surface before it has a chance to set. Too little oil exposes the metal, making sticking more likely.

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The Shield — Heat and Oil

The foundation of cast iron cooking is the shield — keeping food from bonding directly to the metal surface. Heat and oil create it together.

A properly preheated pan instantly sears and sets the surface of the food the moment it makes contact. Oil gets between the food and the pan, preventing direct contact. Neither works alone — only together do they form the shield.

Heat the pan until just before it starts to smoke — if you see a faint wisp, lower the heat slightly — then add the oil. When the pan is properly preheated, the oil spreads quickly and smoothly. That’s a sign the temperature is right.

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Protein vs. Carbs — Different Behavior

Food behaves very differently in a cast iron pan depending on what you’re cooking.

Protein

Protein contracts as heat gets through. Even if it sticks at first, it will usually release on its own as the surface sets — as long as the shield is working. Patience is key.

If it still sticks, add a small splash of water, cover with a lid, and let the steam help release it. If needed, turn off the heat and wait. Don’t force it.

Carbs

Starch gelatinizes when exposed to heat and moisture, bonding to the surface of the pan. Unlike protein, the more heat and moisture it gets, the more it sticks.

The shield alone isn’t enough. Two more things are needed.

Moisture Management — Maintaining the Shield
Too much moisture lowers the pan’s temperature and weakens the shield. Keep the surface of the food as dry as possible. Get this wrong, and even the right tool won’t be able to help.

The Right Tool — The Spear
To release carbs that have bonded to the pan, a thin, rigid stainless steel turner is the tool for the job. Silicone is too soft and lacks a sharp edge. Wood is hard but too thick. Neither can cut through the bond between the food and the pan.

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Breaking In and Oil Priming

For a new pan, it helps to do an initial oil treatment. Heat a generous amount of oil in the pan, swirl it to coat the entire surface, then pour the excess back into an oil pot. Oil priming before cooking works the same way. It creates an even film of oil across the surface and helps prevent sticking. I only did this in the early days.

It doesn’t have to be perfect. What matters is building up layers over time through regular use.

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Closing

Cast iron isn’t difficult. The basics are heat, oil, and a little patience.
For carbs, moisture management and the right tool matter just as much. Once you understand how different foods behave, cast iron becomes much easier to use.

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Related Articles

→ River Light Cast Iron Pan from Japan — A Simple Pan I Keep Using
→ How to Care for a Cast Iron Pan
→ How to Cook Gyoza in a Cast Iron Pan — Why It Sticks and What to 　Do About It
→How I Made Fried Rice in a Cast Iron Pan — What Gyoza Taught Me